Clamp-screw lock



M1141 H. J. HILLBO'RN CLAMP SCREW'JLOCK Filed Sept. 18, 1926 [NV EN TOR.

ATTORNEY.

HERBERT T. HILLHORN, OF HILWAUKEE,.WISCONSDT, ASSIGNOR COIPANY, 01' IILWAUKEE, WIBGONSIK, A CORPORATION crimson-m LOOK Application fllcd september 1a, 1926. Serial in. 138,221.

My invention relates to improvements in clamp screw locks.

It is the purpose of my in vcntion not only a to provide a lock to prevent the rotation of'a 5 clamp Screw through vibration of the mechanism of which it is a part, but to provide a positive lock to prevent theft of objects clamped to larger or stationary bodies by means of rotatable screw clamps.

10 It is a further object of my invention to apply a tumbler lock to a retaining bolt which is actuated against a clamp screw to prevent rotation thereof.

In the drawings:

F igure 1 shows an application of my lock mechanism to the clamping screw of an outboard boat motor bracket.

Figure 2 is a section taken on line 2-2 of Fi are 1.

* igure 3 is a view similar to Figure 2 and showing a lock bolt in disengaged position.

Figure 4 is a view showing the relation of 1thaktumblerlock plug to the latch bolt of my Like parts are identified by the same rcference characters throughout the several views.

In Figure 1 I have shown the transom 1 of a boat upon which clamp bracket 2 of an outard motor is hang. The usual form of clamp screw 6, in threaded engagementwith arm 5 of the motor bracket, is adapted to thrust the s'wivcled clamping member 7 a ainst the inside surface of the transom w an the screw 6 is turned in the proper dimotion by hand pressure upon its winged head 8. This is the usual construction in outboard motor clamps, and it is to the control of the threaded rotation of the clamp screw 6 40 through the arm 5 that my invention is dirooted.

A hole 9 drilled u warclly from the under side of the arm 5 o the bracket 2 receives a latch bolt 10 and a helical sprin 11 which is seated in the extreme inner en of the hole and maintains the bolt under ressure. Bore 9 is intersected by the tappe opening 12 in arm 5 through which the clamping screw 6 is threaded, the ion th of the bolt 10 being such that its reduce extremity 13 is adapted to interact with the surface of the screw. Grooves 14, which extend axially along oposite sides of the threaded clamp bolt 6, are i ormed in the clamp bolt in the manner customary in the formation of key ways, and

rotation of the latch bolt and the clamp screw. When the NW 330 EVIIG'ELUDE MOTCi OF WIStlQIlllllIN.

PATENT. over when the clamp screw is rotated to bring any of these grooves or key ways into lhi gristpi r with the reduced portion 13 oi the latch. bolt 10, such portion will enter the groove under the pressure of spring 11.

T to latch bolt 10 has a portion cut away at 15 to provide shoulders 16 against which the oval-shaped portion 17 of the lock plug; 18 will act. The plug 18 forms a central rotatable part of t e lock 19, and the hey align an able tumblers 20 are adapted to engage with the cylinder 21 when the key 22 is rctracted from the plug.

As shown in Figures 2 and 3, the eccentric portion 17 of the plug 18 co-acts with the shoulders ltl'of the latch bolt 10 during; plug rotation in such manner as to control the spring actuation of the latch bolt. I t will be seen particularly in the structure shown in Figure 1 that the eccentric 17 is also adapted to co-act with the surface 16' to prevent the thereby retainmg; the extended portion 13 thereof in proper alignment for registry with the grooves of eccentric 17 of the plug is in the position shown in Flflllc 2, the bolt will ride upon the surface 0 the screw, and the spring 11 will force the extremity 13 of the latch bolt into one of the grooves 14 whenever the screw is rotated to bring a groove therebencath. The withdrawal of the key 22 from the tumbler lock will then actuate the tumblers 20 to the end that they will co-act with the cylinder 21 and prevent rotation of the plug 17 until the proper key is again inserted in the lock.

Insertion of the key in the lock will ali the tumblers and permit the rotation of t e plug b means of the key, so that the eccentrio wi I act to force the bolt upward as shown in Figure 3 and release the clamp screw 6 for free rotation in its threaded relation with the ban er arm 5. Other forms of locks may easiy be adapted to my structure, and the latch may easily be controlled by the rotat able plugs of such other locks or may be controlled by the rotation or insertion of any of the many varieties of keys with which such locks may be operable.

A lock is, therefore, provided by my invention so that the outboard motor or other object clampin 'ly engaged by a screw may be securely 00 ed in such manner that the clamp will not only be prevented from loos I ening through vibration of the parts, but

" vided with intersecting bores, .0

persons to remove the clamped ar-,

claim: a

The combination with an outboard moor bracket having a clamp arm, of a screw threaded throu" it said arm and provided with a recess, a atch bolt'housed within saidarm and havin a portion receivable in said recess, and a loc operatively'mounted in .said

arm and havin a plug interactin with th latch bolt for t e operation thereo v 2. The combination with a clamp arm pro-' a clamp screw in threaded engagement with one of said bores and provided'with an axial groove, a reciprocable latchtbolt iii-another of said a lockin o rativefconnection with for the ad ustmentthereof.- ;g:-

said bolt 3. The combination'with a braclret haviniza clam 'armlof a-clam screw, in shouldered 1m bolth abovesaid screw and reci rocably adapted for interaction therewith to 1; the position therep of, and a'rotatable lock plu "accessible from :the exterior of said arm and within with an eccentricinterac'tin shoulder of said latch bolt fo'r theadyustment provided there thereof. :i- 4- 7T vided withintersecting, bores, 30 a clamp "fl as screw in threaded engagement with one of said bores and rovided with anaxial groove,

" a reciprocable atch bolt in janotherofsaid V ured against the eilorts of unaution therewith to fix theoused within said arm with a.

bores and inaccessible for manual control 'said bolt being adapted to interact with said 4 rom its support.

groove to revent rotation of the screw, a spring urging said bolt toward said oove, and a lock in operative control of said It.

5. The combination with a clam screw, of a shouldered latch bolt adapted or interaction thereof, a spri g adapted to force t e latch bolt into into ction with the screw, and a rotatable lock' lug rovided with an eccentric interf'actab e wit 1 a shoulder of said latch bolt to withdraw said latch bolt from interaction.

with the clamp screw.

. 6; In combination with a clamp arm provided with intersecting bores, of a clamp I ,screw in threaded en gement with one of bores and adapted Zto finteract. with said groove to prevent'rotation oi the screw and.

said bores and provide with an axial l latch bolt cut away to provide shoulders and ":ilat surface, and a lock provided with a luF and an eccentric co-acting with the latch bo t "'ior ad'ustment thereof and to thin c said oblong end.

7. In a clamp having a clamping arm proyidcd with intersecting bores and an axially grooved clamp screw in threaded engagement with one of said bores the combination with v a latch. bolt reciprocable in another of said bores and rticcivabls in groovg, said bolt having an e on ate axia y extcn in l in said of clock contro led eccentric d recess and en ageable with the walls thereof. fiERBERT J. HILLBORN.

prevent rota- 

